. Scientific Frontline

Thursday, December 15, 2022

Frequent genetic cause of late-onset ataxia uncovered by a Quebec-led international collaboration

Photo Credit: whitfieldink

Discovery will improve diagnosis and open treatment possibilities for thousands of people with this debilitating neurodegenerative condition worldwide

A new study published in the New England Journal of Medicine reports the identification of a previously unknown genetic cause of a late-onset cerebellar ataxia, a discovery that will improve diagnosis and open new treatment avenues for this progressive condition.

Late-onset cerebellar ataxias (LOCA) are a heterogeneous group of neurodegenerative diseases that manifest in adulthood with unsteadiness. One to three in 100,000 people worldwide will develop a late-onset ataxia. Until recently, most patients with late-onset ataxia had remained without a genetic diagnosis.

An international team led by Dr. Bernard Brais, a neurologist and researcher at The Neuro (Montreal Neurological Institute-Hospital) of McGill University and Dr. Stephan Züchner of the University of Miami’s Miller School of Medicine, in collaboration with neurologists from the Universities of Montreal and Sherbrooke, studied a group of 66 Quebec patients from different families who had late-onset ataxia for which an underlying genetic cause had not yet been found. Using the most advanced genetic technologies, the team found that 40 (61 per cent) of the patients carried the same novel disease-causing variant in the gene FGF14, making it the most common genetic cause of late-onset ataxia in Quebec. They found that a small stretch of repetitive DNA underwent a large size increase in patients, a phenomenon known as repeat expansion.

Comet Impacts Could Bring Ingredients for Life to Europa’s Ocean

An artist's concept of a comet or asteroid impact on Jupiter's moon Europa.
Illustration Credit: NASA/JPL-Caltech

Comet strikes on Jupiter’s moon Europa could help transport critical ingredients for life found on the moon’s surface to its hidden ocean of liquid water — even if the impacts don’t punch completely through the moon’s icy shell.

The discovery comes from a study led by researchers at The University of Texas at Austin, where researchers developed a computer model to observe what happens after a comet or asteroid strikes the ice shell, which is estimated to be tens of kilometers thick.

The model shows that if an impact can make it at least halfway through the moon’s ice shell, the heated meltwater it generates will sink through the rest of the ice, bringing oxidants — a class of chemicals required for life — from the surface to the ocean, where they could help sustain any potential life in the sheltered waters.

The researchers compared the steady sinking of the massive melt chamber to a foundering ship.

NASA’s Webb Unveils Young Stars in Early Stages of Formation

Image of the Cosmic Cliffs, a region at the edge of a gigantic, gaseous cavity within NGC 3324, captured by Webb’s Near-Infrared Camera (NIRCam), with compass arrows, scale bar, and color key for reference.  The north and east compass arrows show the orientation of the image on the sky. Note that the relationship between north and east on the sky (as seen from below) is flipped relative to direction arrows on a map of the ground (as seen from above).  The scale bar is labeled in light-years, which is the distance that light travels in one Earth-year. It takes 2 years for light to travel a distance equal to the length of the bar. One light-year is equal to about 5.88 trillion miles or 9.46 trillion kilometers.  This image shows invisible near-infrared wavelengths of light that have been translated into visible-light colors. The color key shows which NIRCam filters were used when collecting the light. The color of each filter name is the visible light color used to represent the infrared light that passes through that filter.  Webb’s NIRCam was built by a team at the University of Arizona and Lockheed Martin’s Advanced Technology Center. 
Hi-Res Zoomable Image
Credits SCIENCE: Megan Reiter (Rice University) IMAGE: NASA, ESA, CSA, STScI IMAGE PROCESSING: Joseph DePasquale (STScI), Anton M. Koekemoer (STScI)

Scientists taking a “deep dive” into one of Webb’s iconic first images have discovered dozens of energetic jets and outflows from young stars previously hidden by dust clouds. The discovery marks the beginning of a new era of investigating how stars like our Sun form, and how the radiation from nearby massive stars might affect the development of planets.

The Cosmic Cliffs, a region at the edge of a gigantic, gaseous cavity within the star cluster NGC 3324, has long intrigued astronomers as a hotbed for star formation. While well-studied by the Hubble Space Telescope, many details of star formation in NGC 3324 remain hidden at visible-light wavelengths. Webb is perfectly primed to tease out these long-sought-after details since it is built to detect jets and outflows seen only in the infrared at high resolution. Webb’s capabilities also allow researchers to track the movement of other features previously captured by Hubble.

Scandinavian wolves carry many harmful mutations

Researchers from Uppsala University have discovered that each wolf in the Scandinavian wolf population has an average of approximately 100,000 harmful mutations across the entire genome.
Photo Credit: Hans Veth

In a new scientific study, researchers at Uppsala University have shown that Scandinavian wolves carry around 100,000 harmful mutations in their genome. As long as the harmful mutations can be compensated by a healthy genetic variant, this does not need to pose a problem. However, as there has been a high level of inbreeding in the wolf population, the occurrence of double harmful variants has increased with each generation.

Mutations occur constantly in all organisms, and many of the changes can have a harmful effect on survival and reproduction. However, as there are two copies of each chromosome, individuals are often protected by one of the copies remaining intact. But in the case of inbreeding, it can happen that individuals carry two copies of a harmful mutation, which leads to a problem known as inbreeding depression.

Biodegradable medical gowns may add to greenhouse gas

Photo Credit: National Cancer Institute

The use of disposable plasticized medical gowns – both conventional and biodegradable – has surged since the onset of the COVID-19 pandemic. Landfills now brim with them.

Because the biodegradable version decomposes faster than conventional gowns, popular wisdom held that it offers a greener option by less space use and chronic emissions in landfills.

That wisdom may be wrong.

Biodegradable medical gowns actually introduce harsh greenhouse gas discharge problems, according to new research published Dec. 20 in the Journal of Cleaner Production.

“There’s no magic bullet to this problem,” said Fengqi You, the Roxanne E. and Michael J. Zak Professor in Energy Systems Engineering, in the Smith School of Chemical and Biomolecular Engineering.

“Plasticized conventional medical gowns take many years to break down and the biodegradable gowns degrade much faster, but they produce gas emissions faster like added methane and carbon dioxide than regular ones in a landfill,” said You, who is a senior faculty fellow in the Cornell Atkinson Center for Sustainability. “Maybe the conventional gowns is not so bad.”

Scientists find iron cycling key to permafrost greenhouse gas emissions

Iron content gives a reddish hue to an area of ponded water in the Arctic permafrost. ORNL scientists are exploring the importance of the iron cycle on how greenhouse gases are released from thawing Arctic soils.
Photo Credit: David Graham/ORNL, U.S. Dept. of Energy

The interaction of elemental iron with the vast stores of carbon locked away in Arctic soils is key to how greenhouse gases are emitted during thawing and should be included in models used to predict Earth’s climate, Oak Ridge National Laboratory scientists found.

Researchers set out to explore and model the chemistry going on as the Arctic permafrost thaws in response to global warming. Northern permafrost soils contain an estimated 1,460 billion to 1,600 billion metric tons of organic carbon — about twice as much as in the atmosphere, according to the National Oceanic and Atmospheric Administration.

Chemical processes in the soil control how organic matter decomposes and is stored in soils and whether it converts to carbon dioxide or the more powerful greenhouse gas methane when released into the atmosphere.

Arctic soils are typically organic-rich and often have a high iron content, frequently visible as rusty deposits in flooded soils in the region, said ORNL modeler and principal investigator Benjamin Sulman. But current Earth system models do not take iron cycling into account when predicting the climate-warming potential of thawing permafrost.

Researchers aim to explore how matter gets its mass by confining quarks

STAR chamber
The research on quark confinement was inspired in part by nuclear research carried out at the Brookhaven National Laboratory in the U.S. Pictured here is a giant particle detector that can image subatomic interactions. This apparatus is investigating rapidly rotating quark matter.
Full Resolution Image
Image Credit: Brookhaven National Laboratory CC BY-NC-ND 2.0

A new way to study quarks, one of the building blocks of the protons and neutrons that make up atomic nuclei, is proposed. This has never been done before and doing so would help answer many fundamental questions in physics. In particular, researchers could use the new approach to determine how matter gets its mass.

The study of matter can seem a bit like opening a stack of Russian matryoshka dolls, each level down revealing another familiar, yet different, arrangement of components smaller and harder to explore than the one before. On our everyday scale, we have objects we can see and touch. Whether water in a glass or the glass itself, these are mostly arrangements of molecules too small to see. The tools of physics (microscopes, particle accelerators, and so forth) let us peer deeper to reveal molecules are made from atoms. But it doesn’t stop there — atoms are made from a nucleus surrounded by electrons.

3D imaging of shark embryos reveals evolution of pelvic fins

Photo Credit: Marcelo Cidrack

Curtin University researchers have revealed how the pelvic fins of fish such as sharks and chimaeras have evolved from their sudden appearance in the fossil record over 410 million years ago.

The team used CT scanning and 3D modelling to study the growth of pelvic fins in fish embryos to help us understand how the skeleton of these fins changed over evolutionary history.

Lead author and PhD candidate Jacob Pears from Curtin’s School of Molecular and Life Sciences said the research showed what the development of modern animals can tell us about their evolution.

“Our work focused on cartilaginous fish and in particular looked at the pelvic fins of elephant sharks. The fine detail from our imaging revealed the basipterygium (pelvic fin bar), which like the femur and tibia in humans, were formed by the fusion of fin radials during early embryonic development,” Mr. Pears said.

Early humans may have first walked upright in the trees

Photo Credit: Alexa

Human bipedalism – walking upright on two legs – may have evolved in trees, and not on the ground as previously thought, according to a new study involving UCL researchers.

In the study, published in the journal Science Advances, researchers from UCL, the University of Kent, and Duke University, USA, explored the behaviors of wild chimpanzees - our closest living relative - living in the Issa Valley of western Tanzania, within the region of the East African Rift Valley.

Known as ‘savanna-mosaic’ – a mix of dry open land with few trees and patches of dense forest - the chimpanzees’ habitat is very similar to that of our earliest human ancestors and was chosen to enable the scientists to explore whether the openness of this type of landscape could have encouraged bipedalism in hominins.

The study is the first of its kind to explore if savanna-mosaic habitats would account for increased time spent on the ground by the Issa chimpanzees, and compares their behavior to other studies on their solely forest-dwelling cousins in other parts of Africa.

Overall, the study found that the Issa chimpanzees spent as much time in the trees as other chimpanzees living in dense forests, despite their more open habitat, and were not more terrestrial (land-based) as expected.

Scientists Have Figured Out How to Use Silicone to Protect against Radiation

Scientists plan to investigate a broader set of materials that can attenuate radiation.
Photo Credit: Anastasia Farafontova

An international team of scientists has developed a material that can be used in the future as radiation protection against gamma radiation, in particular, it can be used to create radiation protection for Nuclear Power Station workers. The new material is based on silicone using zinc oxide nano powder additions. The results of research on the new material and its properties have been published in the journal Optical Materials. Physicists from Russia (Ural Federal University), Jordan, and Turkey took part in the work.

"Gamma radiation is widespread in the health care, food and aerospace industries. Excessive exposure can be harmful to human health. Gamma radiation is now attenuated or absorbed using lead, concrete, lead-oxide, tungsten, or tin-based materials. These protective materials are not always convenient to use as protection against gamma rays. In addition, they are expensive, too heavy and highly toxic to humans and the environment. This is why it is important to find new materials and optimize their composition for radiation protection, which will ensure human and environmental safety," says Oleg Tashlykov, Associate Professor at the Department of Nuclear Power Plants and Renewable Energy Sources at UrFU.

Quenchbody Immunosensors Pave the Way to Quick and Sensitive COVID-19 Diagnostics


A new immunosensor based on Quenchbody technology shows great potential as a fast, inexpensive, and convenient tool to detect SARS-CoV-2. Developed by scientists at Tokyo Institute of Technology (Tokyo Tech) and Tokyo Medical and Dental University (TMDU), this highly efficient diagnostic approach will be useful not only for point-of-care testing, but also for high-throughput epidemiological studies of COVID-19 and other emerging infectious diseases.

The double-tagged Quenchbody immunosensor becomes fluorescent when its target antigen—the nucleocapsid protein from SARS-CoV-2—binds at the antigen-binding region of the antibody fragments. This approach is fast, cost-effective, and convenient to use in practice, making it ideal for point-of-care testing as well as batch processing of patient samples. 

The incredibly fast spread of COVID-19 throughout the world brought to light a very important fact: we need better methods to diagnose infectious diseases quickly and efficiently. During the early months of the pandemic, polymerase chain reaction (PCR) tests were one of the most widely used techniques to detect COVID-19. However, these viral RNA-based techniques require expensive equipment and reaction times longer than an hour, which renders them less than ideal for point-of-care testing.

Early green, early brown – climate change leads to earlier senescence in alpine plants

Alpine plants that start to grow earlier also start to age earlier. As is the case with the alpine vegetation in these containers, which were exposed to summer weather several months before the snow melted photograph taken in July
Photo Credit: P. Möhl

Global warming is leading to longer growing seasons worldwide, with many plants growing earlier in spring and continuing longer in autumn thanks to warmer temperatures—so is the general opinion. Now, however, plant ecologists at the University of Basel have been able to show that this is not the case for the most common type of alpine grassland in the European Alps, where an earlier start leads to earlier aging and leaves the grassland brown for months.

Spring 2022 was extremely warm, giving many plants an early start to the growing season. And the Swiss Alps were no exception, with the snow cover melting early and the underlying vegetation being quickly roused into growth. Researchers at the Department of Environmental Sciences at the University of Basel have investigated how such an early start affects the plants’ further development.

For their study, they removed intact blocks of alpine grassland and placed them in walk-in climate chambers at Basel’s Botanical Institute. Here, they left the vegetation to overwinter artificially in cold darkness, and then switched some of the blocks to summer conditions in February. A second group was left in the cold dark until April, before summer was introduced here as well. The researchers compared the growth and aging of these plants with their neighbors growing naturally at an elevation of 2,500 meters, which did not emerge from the snow until late June.

Wednesday, December 14, 2022

With Discovery, Oxygen's Role in Growth of Tumors Reconsidered

Structure of the HIF1A protein. Based on PyMOL rendering of PDB 1h2k Illustration
Credit: Emw
CC BY-SA 3.0

Yale researchers have made a discovery that changes conventional thinking about the role that oxygen plays in the growth of tumors—an area of cancer research that has been intensely studied in recent years.

The results, from the lab of Andre Levchenko, the John C. Malone Professor of Biomedical Engineering, are published in Cell Systems. Other groups collaborating on this study were directed by Chi V. Dang (Johns Hopkins University) and Kshitiz (University of Connecticut).

When tumors start running out of oxygen, they can switch on hypoxia-inducible factor (HIF-1alpha)—a transcription factor, which is a protein that controls the activity of genes. As a result of HIF-1alpha activation, the expression of hundreds of genes can change and dramatically alter the behavior of cancer cells. Although the increase in HIF-1alpha is thought to be steady, the new study led by Levchenko discovered that the levels of this molecule can also repeatedly rise and fall in small groups of cells, particularly in areas of high cell density. The effects of this oscillation are profound, as it allows cancer cells starving for oxygen to resume division and growth. It can also promote pro-cancer genes and inhibit anti-cancer genes.

Paris Agreement temperature targets may worsen climate injustice for many island states

A comparison of global greenhouse gas emissions from 1990 – 2018 shows the low emissions contribution of AOSIS nations (blue) and increasing levels of total global emissions (red).
Illustration Credit: Sadai et al., 10.1029/2022EF002940

While the world focuses on limiting the rise in global temperature to 1.5 or 2 degrees Celsius over the preindustrial average, increasing meltwater from ice sheets presents an existential threat to the viability of island and coastal nations throughout the world. Now, research from the University of Massachusetts Amherst, recently published in the journal Earth’s Future, shows that even the most optimistic temperature targets can lead to catastrophic sea-level rise, which has already begun and will affect low-lying nations for generations to come.

While rising temperatures are having many deleterious effects on global ecosystems, economies and human wellbeing, an interdisciplinary team of researchers at the University of Massachusetts emphasize that temperature alone is not a sufficient basis for climate policy. 

Laser controls ultra-fast water switches

The water is fanned out by a specially developed nozzle. Then the laser is passed through.
Photo Credit: Adrian Buchmann

Researchers are introducing a completely new concept for switches with unprecedented speed.

Researchers at the Ruhr University Bochum have developed an ultra-fast circuit based on water. Thanks to a short but strong laser pulse, the water can be reached within less than a billionth of a second (10th-12 Seconds) in a conductive state and behaves almost like a metal during this time. This makes the circuit faster than the fastest known switching speed of a semiconductor to date. Adrian Buchmann, Dr. Claudius Hoberg and Dr. Fabio Novelli from the Ruhr Explores Solvation Cluster of Excellence, in short RESOLV, report in the journal APL Photonics December 2022.

Laser lets the water behave like a fast switch

All computer arithmetic operations are based on circuits. The speed at which a component can switch between states zero and one ultimately determines the speed of the computer. Semiconductors that enable electrical circuits are installed in current computers. "They are naturally limited in speed," explains Claudius Hoberg.

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